Although various known clinical analyzers for chemical, immunochemical and biological testing of samples are available, clinical technology is rapidly changing due to increasing demands in the clinical laboratory to provide new levels of service. These new levels of service must be more cost effective to decrease the operating expenditures such as labor cost and the like, and must provide shorter turnaround time of test results. Modernization of analytical apparatus and procedure demands consolidation of workstations to meet the growing challenge placed on clinical laboratories.
Generally, analysis of a test sample involves the reaction of test samples with one or more reagents with respect to one or more analytes wherein it is frequently desired that the analysis be performed on a selective basis with respect to each test sample. Automated clinical analysis systems analyze a test sample for one or more characteristics. Automated clinical analyzers also provide results much more rapidly while frequently avoiding operator or technician error, thus placing emphasis on accuracy and repeatability of a variety of tests. Automated clinical analyzers presently available for routine laboratory tests include a transport or conveyor system designed to transport containers of sample liquids between various operating stations.
Some of the presently available automated clinical analyzers, such as automated immunoassay analyzers, utilize procedures involving a variety of different assay steps. A robotic arm automatically processes the test samples with a probe and a carousel, or robotic track, which positions the samples for processing. A typical analyzer has a sample probe to sample fluids and deposit the samples in a reaction vessel. One or more reagents are added to the vessel using reagent probes. Sample and reagent probe arms include probes that can be moved between sample or reagent locations, the reagent vessel and wash stations.
Clinical chemistry and immunoassay analyzers have traditionally been standalone systems. These systems can be combined using a common transport system to provide a more efficient integrated system. Previous standalone chemistry analyzers did not require sample-to-sample carryover performance requirements of an integrated clinical chemistry and immunoassay system. As laboratories integrate automated analytical systems, reduction of between-sample carryover becomes a critical goal. Many companies have elected to overcome this problem through use of disposable probe tips, but this approach is costly, wasteful and less reliable. Another safeguard is to prioritize test sequencing such that immunoassay sampling is done prior to all chemistry tests. This approach impacts chemistry turnaround time and lowers total workflow throughput. Yet another method to reduce sample carryover is to flush the system with large amounts of fluids (buffer, water, detergents).
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a reduction in sample carryover in clinical test equipment.